The measurement of ocular blood flow is essential to improve the understanding of several diseases afflicting the eye, including glaucoma. One of the hypotheses for the cause of glaucoma is that the optic nerve tissue is damaged by insufficient blood flow, because of a deficiency in the tissue's ability to regulate its own blood supply in response to increased intraocular pressure. A clinically useful blood flow measurement tool is necessary to fully investigate this hypothesis. The proposed research builds on the results found during Phase I of this project, in which a confocal laser Doppler blood flow measuring device has been developed and was shown to allow quantitative measurements of artificially induced changes in blood flow. Work during the Phase II of this project is intended to broaden the retinal area that can be investigated during a single measurement, improve the instrument's ease of use and investigate its clinical applicability by using it to determine the degree of (predicted) impact disease processes such as glaucoma, diabetic retinopathy and age related macular degeneration have on retinal blood flow. PROPOSED COMMERCIAL APPLICATION: This research may lead to the development of a non-invasive, clinical instrument for depth-resolved measurements of optic nerve bloodflow and optic nerve topography through undilated pupils. Such an instrument would be very useful in the clinical areas of early detection and monitoring of disease processes and their treatment.